Writing instrument



July 30, 1957 E. D. MUNsoN WRITING INSTRUMENT Filed Aug. 1s, 195s t llllilllfll I lllllIllllllllllllllllfllll FIGS.

lll/41 nventor EVERIS D. MUNSON I Gttorneg 2,800,881 Patented -July 30, 19,57

WRITING lNSTRUh/[ENT Everis D. 'Muusorn St. Paul, Minn., kassigrror to Brown & Bigelow, St. Paul, Minn., a corporation of Minnesota Application August 13, 1953, Serial N o. 373,993

1 Claim. (Cl. 1Z0-42.03)

My invention relates to an improvement in writing instruments, and more particularly to a type wherein the `ball point Writing tip may be projected from the casing by pressing a knob-like member extending from the rear of the casing which causes the Writing tip to be projected out ofthe writing end of the instrument. A spring catch *positioned within the casingengages the shoulder to hold j the writing vtip of the ball point pen projecting from the barrel in "writingposition It is a feature to provide a ball point pen or writing Vinstrument with means for releasing the spring catch within the casing of the pen, whereupon a coil spring Vwithin the casing automatically withdraws the writing 'tip of the pen back into the barrel where it is protected 'and' the writing pen of the barrel of the pen acts as a sheath to cover the writing ball of the pen.

This writing instrument is particularly directed to the Vball point type where a small steel ball is mounted in a reduced tubular end of the ink reservoir. The ink reservoir may be made of metal or plastic, such as polyethylene. When the ink reservoir is made of flexible polyethylene plastic material or vinyl plastic or a similar material, this material may be transparent or translucent and thus provides means so that the ink is visible in the reservoir tube. Where the plastic reservoir tube is transparent or translucent the user or" the pen can check from timel to time to determine just how much ink is left in the reservoir.

A feature of this writing instrument resides in providing a frictional means for engagement of the rear end of the plastic reservoir tube, which holds the ink reservoir tube within the operating mechanism, which moves the tube forward and backward in the casing in the operation of exposing the=writing tipand'in concealing the -same in the barrel of the instrument.

'It is -.a feature to connethe .spring catch for holding then ink reservoir in writing position and the spring means for forcing the ink reservoir into a backward position within the rear end of the writing instrument.

lt is a further feature to provide a writing instrument wherein the front end of the barrel can be removed from the rear portion so that a new ink reservoir can be placed in the writing instrument when the old one has been removed and discarded. In this construction the operating mechanism, including the coil spring for returning the writing tip into the barrel to conceal the same, together with the spring release or catch which holds the writing tip and the ink reservoir in writing position, are all confined in the rear portion of the writing instrument so that when the writing instrument is taken apart to remove an old ink reservoir and add a new one, none of the working parts of the pen are exposed or can become disassembled. The rear knob, however, projects from the rear end of the casing of the Writing instrument and is exposed so that it can be depressed when it is desired to project the writing point of the ink reservoir into writing position.

The operating mechanism in the rear of the Writing instrument which holds `the writingball in writing position includes .a spring catch .having a band-like collar which extends around thetubular portion of the operating vmeans which frictionally holds the rearend of theink reservoir. When this tubular end is pushed in by the I' knob projecting outof the rearof the casing, the bandlike spring catch will move into position to engage a'shoulder on the same, holding the ink reservoir in writing position while desired for writing. The pocket clip, which normally holds the pen in ones pocket, is mounted on the casing of the instrument witha spring fornormally holding the pocket engaging end of the clip in operative position. The rear end of the clip projects into the `.path of the collar-like spring catch; thus, when it is desired to releasethe collar spring catch in the writingv inbackward. position automatically by the coil spring.

In the 'drawings forming part of the specification:

Figurerl is an enlarged longitudinal section of Lmy writing instrument.

Figure 2 is a section of the upper rear end of thewriting instrument with the operating knob pressed inwardly and held by the spring collar catch.

Figure 3 is a perspective View of the collar spring catch removedfrom the barrel of the writing instrument.

Figure 4 is a perspective View of the tubular member which engages the rear of the ink reservoir to frictionally support the same and also the integrallyformed knob on the rear end thereof.

Figure. 5 isa section on the line 5-'5 of Figure 1 in the direction ofthe arrows. j

The writing instrument A is illustrated in the drawings with a rear casing portion 10 and a front removable portion 11. v

The ink reservoir B, which is normally concealed within the casing'portions `10 and 111, is preferablylformed of `exible plastic, such as Vinylite, polyethylene or a simi- 4which is mounted a ball'13. The ball 13 maybe of steel Vor any'other suitable material wherein a .truespherical ball is provided and mounted in the front endof the tube vr12 sothat it will freely rotate andact asj antink carrier. v

jThetube 12, 'carrying' the ball'` 13, vmay be mountedin f the forward end of'the'ink reservoir B in any suitable manner, such as supporting the tube 12 frictionally within the forward end of the plastic tube B, threading it in the same or otherwise sealing the tube 12 to the ink reservoir tube B. The tube 12 normally is made of brass or similar material and has formed therein a suitable socket for the ball 13.

The ink reservoir B is in the form of a long tube and when formed of translucent or transparent plastic material, the tube is ilexible and as the ink is used up from the same by the writing ball 13, the operator may readily observe just how much ink remains within the reservoir. This is important because it keeps the operator of the instrument A fully informed at any time that the writer chooses to inform himself of how much ink remains therein. The ink reservoir tube B, with its writing end 12, form a unit which may be removed and replaced with a new unit whenever desired.

When the operator places the ink reservoir B Within the pen A, the rear end of the reservoir B is adapted to be inserted in the plastic tubular member 14 which is 'formed with anink-'reservoirreceiving chamber 15, the

inner end 15' of whichis reduced in diameter to frictionally engage the inner end of the ink reservoirtube B. The tubularplastic member 16v is positioned within the frnetal rear end 17 of the casing of the writinginstrument `VA landY is fixed therein with a projecting threaded end V18 /hicli engages with theY front plastic tubular lendllrgoftheV v-the rear end of the clip and ,thespringfurged endonthe other end Yofthe clip. ,Y l t t A coil spring 22'V 's positioned in' thetubular portion 16 "and is, adapted to` bear against the Yforward end 23 of the tube 14 tonormally'hold Vthe tube 14 in rearward position in thepen A, as illustrated in Figure l. 'I'he rear end of thettube 14 is formed with an 'integral'operating 'knob ,14whi'ch normally projects Vout of Vthe rearend -portion 17 of the casing of the pen. An air'gslot 24 is formed in one side vof the tubular member V14 andra re- 1`inforcing metal strip 25 is anchored in the tubular portion' 14, the purpose of which will be'hereinafter de-V scribed. t t

I provide a collar spring catch 26, illustrated,1removed from the writing instrument in Figure 3, Whichisformed with Ia collar catch end 27, a tongue 28 and a spring shank Varm 29. The spring arm 29 is formed with an inturned end which engages under a shoulder formed in the tube 16, to anchor the spring arm 29 in place, extending between the tubular portion 16 and the outer metal cas- 'ing 17. Y In operation, the writing ball 13 and the tubular end V12 of the reservoir B are projected out of the writing end Vofthe tubular member 11 by pressing on theknob 14v rat'the'rear of the instrument A. ThisY operation causes 'Y thertongueV `28 to engage on the'shoulder 31 .when the ing ball 13 projecting lout of the casing of the instrument.

Figure 2 showsrthe knob 14' depressedtand the Lspring collarcatch 26 .engaging the shoulder 31. In this po sition the coil spring 22 is compressed. Y

When vit is desired to movethe Writing ball 173 YbackY `into` the casing Vof the instrument, to conceal the lsame,y Y the free end'20 of the clip C is pressed inward against Writing ball is covered by the tubular forward end ofr the portion 11 and the ball 13 is prevented from getting ink on the users pocket or clothes.

The collar catch 26 is of primary importance in that it provides a simple means of engaging the shoulder 31 to hold the ink reservoir inY writing position and forms a means so that the free end 20 of the pocket clip can'ref lease the spring catch 26 to cause the spring 22 to automatically conceal the writing ball 13. Y .n

The simple Yfeatures of my pen .willbetapparent from the foregoing description and the illustrations in the drawings. my pen is illustrated and described, it is to be understood that changes in the detailed construction may be madeV within the scope of the invention as claimed.

l claim: In a writing instrument, a rear outer casing, an inner inkcartridge supporting tube slidable within said outer casing open at Vthe frontl end thereof and having an air slot formed therein near therear thereof, an operatingk casing, spring means contained Vwithin said enlargedk bore of said bushing and abutting Ythe lower end of said supporting tube slidably urging said tube generally` in an outwardly position, `a spring arm positioned within said outer casing having a continuous collarA catch formed on the rear end thereof, an inturned tongue integral with said spring arm at the rear thereof and engageable with said shoulder on said ink -cartridge supporting tube to hold "said supporting tube in an inwardly position, a Spring clip pivotally attached to said rear outer casing and having a depressible rear'end engageable with said collar catch on said spring arm to release said tongue from said in k Ycartridge supporting tube when said clip is depressed, Aa

hollow front casing threadably'engageable with said bushving member having an aperture formed therein Vin the A front thereof, and a ilexible ink reservoirhaving a Writing tip attached thereto at the front thereof and frictionally 'engageable within said ink cartridge supporting-tube at 'the rear thereof. Y l

References Cited in the tile of this patent FOREIGN PATENTS Germany Mar. 19,*71890 Great Britain Aug. '16, 1950 While the preferred form of the construction ofV 

